The present invention relates to a converting press for paper or cardboard sheets including a waste stripping station with a tool supporting chase comprising a pair of horizontal transverse rails to which is secured an upper stripping tool.
The present invention also relates to a converting press for paper or cardboard sheets including a blanking station with a tool supporting chase comprising a pair of horizontal transverse rails, to which is secured an upper blanking tool.
The present invention also relates to a converting press for paper or cardboard sheets, including at the same time a waste stripping station and a blanking station such as described above.
The converting presses for paper, solid board or corrugated board are using for each order a whole range of specific converting tools for a specific work. Such a whole range of tools includes specifically:
a makeready protection plate
a makeready sheet
a cutting die
a cutting plate comprising the cutting counterparts
a waste upper stripping tool
a central stripping board
a lower stripping frame comprising telescopic tools for waste capture
an upper blanking tool
a lower blanking tool.
The waste upper stripping tool as well as the upper blanking tool can be a pull-out frame of standard size, whose front and back sides show profiles securing to and sliding onto profiled fastening devices, such as secured transverse rails and interdependent from the reference stations. The terms xe2x80x9clongitudinalxe2x80x9d and xe2x80x9ctransversexe2x80x9d when the direction of a body is concerned, xe2x80x9cfrontxe2x80x9d, xe2x80x9cbackxe2x80x9d and xe2x80x9clateralxe2x80x9d when a side of a station is concerned, are used with reference to the way of run of the sheets in the machine. The pull-out frame can include several crossbars, on whose are secured a range of strippers. The locations of the crossbars and the strippers into the pull-out frame are subject to change and have to be defined by the work to be achieved. The fitting up of their location is settled outside the machine, preferably on a presetting table, and is dealing with the preparation of the tool. This operation is relatively tiresome, but is achieved in xe2x80x9cmasked timexe2x80x9d independently from the machine in production.
For short and repetitive orders, an upper tool is often used, called die or upper stripping board, respectively die or upper blanking board, made up of a rectangular wooden board, on which are definitively secured strippers of various shapes, corresponding to this specific work. The wooden die itself is assembled inside a pull-out frame. This frame is then settled into the corresponding station. If necessary, the board must be readjusted in position and reinstalled within the frame.
The whole range of the tools mentioned above must be laid out in an extremely precise way in the various stations of the press at the start up of each work. Particularly in the case of short orders, the productivity of the unit depends on a large scale on the rapidity of the positioning and the setting of the tools.
The aim of the present invention is to make easier and faster the positioning and the setting of the upper strippping tool and/or the upper blanking tool, particularly in the case of short and repetitive orders.
This aim is reached with a kind of a converting press as initially defined by the fact that the stripping station comprises a pair of transverse horizontal rails from whose the first one is fixed compared to the tool supporting chase and the second one is movable in a longitudinal direction, and from which the profiles ensure receiving and maintaining, in an operational waste stripping position, either a pull-out frame of an upper stripping tool or an upper stripping board.
This aim is also reached with a kind of a converting press such as the one previously defined by the fact that the blanking station comprises a pair of transverse horizontal rails from whose the first one is fixed compared to the tool supporting chase and the second one is movable in a longitudinal direction, and from which the profiles ensure receiving and maintaining, in an operational blanking position, either a pull-out frame of an upper blanking tool or an upper blanking board.
A waste stripping station and/or a blanking station, according to the invention, allow overcoming the assembly and setting operations of an upper waste stripping board, respectively of an upper blanking board in a pull-out frame. The boards are directly assembled in the station. Resulting from this is a time saving during the preparation of the press between two operations. It also has as a result a saving in the number of the tooling elements to be used. The fact that the second rail is movable allows the spacing adjusting of the pair of rails to various sizes of boards.
The rails of the station can comprise an upper part whose profile is complementary to the profile of a pull-out frame and a lower part whose profile is complementary to the profile of an upper board, the shaped parts of the two rails facing each other.
The rail located in front of the station preferably presents at the level of the shaped part receiving an upper board, a centering block intended for centering into the machine this upper stripping or blanking board. To deal with possible errors of manufacture of the board, the centering block is preferentially transversely adjustable by a micrometric setting device.
The station includes preferably means allowing a push on the movable rail, longitudinally, into the direction of the fixed rail. Acting so, when the upper tool is settled, it is tightly secured between the fixed rail and the movable rail.
The aforesaid means used to push the movable rail forward to the fixed rail can include at least one spring acting with a permanent pushing on the movable rail into the direction of the fixed rail and at least one cylinder, whose setting into operation by the conductor deletes and overcomes the acting of the spring(s), allowing the loosening and the tools changing.
The movable rail, which is preferably the back one, can be held by at least one support, itself or themselves secured on a moving mean, to be used by the conductor. Thus, the station can deal with upper boards of variable sizes. Furthermore, the movable rail can be carried by two holders secured each one onto a rack with longitudinal moving.